Typical commercial hand dishwashing compositions incorporate divalent ions (Mg or Ca) to ensure adequate grease performance in soft water. However, the presence of divalent ions in formulas containing anionic and additional surfactants (e.g., alkyl dimethyl amine oxide, alkyl ethoxylate, alkanoyl glucose amide, alkyl betaines) leads to slower rates of product mixing with water (and hence poor flash foam), poor rinsing, and poor low temperature stability properties. Moreover, preparation of stable dishwashing detergents containing Ca or Mg is very difficult due to the precipitation issues associated with Ca and Mg as pH becomes more basic.
It has now been determined that the use of alkanolamines, such as triethanolamine (TEA) and/or diethanolamines (DEA), as outlined in detail below, with amphoteric surfactants and Mg or Ca ions in dishcare compositions with pH's .about.8.0-10 (as measured as 10% aqueous solution) leads to improved cleaning of tough food stains and removal of grease/oil. Unexpectedly, alkanolamines also improve suds stability in the presence of soils, esp. soils containing fatty acids.
Further, the strong grease removal performance of the combination of alkanolamines as discussed herein allows reduction of Mg or Ca ions from the formulation while maintaining benefits in grease performance.
The alkanolamines of this invention in combination with amphoteric surfactants also provides sensory benefits, such as a "silky" feel to wash liquor and a feeling of "mildness" to the skin. Moreover with the use of alkanolamines, the need for additonal buffers are reduced.
It has now been found thse benefits are achieved through the use of alkanolamines in combination of Mg or Ca ions and amphoterics in higher pH formulations (.about.8.0-10) across a broad range of hardness (8 to&gt;1,000 ppm).